Japan's shrinking population is an obsession of the world, and even in Japan, the issue has raised so many alarms that one paper called for the declaration of a "declining birth-rate state of emergency."

However, the problem isn't unique to Japan, as the island country is to the fertility crisis what low-lying Pacific islands are to the environmental crisis (in terms of rising sea levels). They are both just an early signal of the problems that will affect others later on.

The first time Japan took notice of its low fertility rates was in 1989, when the country's Total Fertility Rate (TFR) was found to be 1.57, much lower than the 2.1 needed for a population to sustain itself.

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Moreover, despite three decades of effort, including task forces and government support program, little has changed, as Japan had a record low FTR of 1.26 in 2005, which it managed to raise to 1.3 in 2021. But Japan isn't the only country to suffer from this, as the phenomenon seems to be tied to an inverse relationship between wealth and fertility. 

Each infertile society is infertile in its own way

In Japan, Okinawa, which is the country's poorest region, consistently has the highest fertility rates, while the rich region of Tokyo has the lowest.  

Almost every country in Europe also lies below the 2.1 level, as Croatia, Portugal and Greece may all decline to similar levels to Japan's in the next three decades.

The issue isn't particular to Japan's problems, be it "low gender equality" that Western pundits have long used to explain the phenomenon, or institutional. For example, Taiwan, which lies in the same geographical region as Japan, and calls itself the most "gender-equal society in Asia", has a TFR rate of 1.08, the worst in the world.

Germany, Italy, Finland, and Hungary, for example also have different gender norms and different public policies to support families and working mothers, but they all share a consistently low TFR, the same goes for the US which has a low fertility rate of 1.66.

The answer to the problem is not suggested to be new policies, according to some experts quoted by Bloomberg, but adaptation. Rather than trying to increase births and change people's minds, the governments in question may want to focus on a mix of integrating women and immigrants to top up the workforce, and help those who lack the opportunity to have children or get married.

Until then, the population of the world's rich countries will continue to deteriorate, as their workforce becomes consistently older, and the young workforce is unable to fill in their shoes.